The only thing that stops the dust is the rain. It’s a sweet reprieve, but there is no middle ground. The land is either as dry as the Betty Ford clinic, or as wet as the ocean floor. Everything can be seen from the ridge overlooking Armadillo as John Marston gently bounces along atop...

Evolve or be destroyed.

The cultural iconography of video games has swallowed mascots whole. The Space Invader sprite is instantly recognizable, whether it can be identified or not. Infinity Gene takes that icon and gives it a cocktail of digital-psychodelic drugs, resulting in a game that will either make you a junkie or make your eyes bleed out. Possibly both.

Infinity Gene starts out with the restricted movement, ancient graphics, and mono sound only the most advanced arcade boards could allow in 1978. Infinity Gene's stage zero cuts to a quote from Charles Darwin: "It is not the strongest species that survive, nor the most intelligent, but the ones most responsive to change." Things evolve briskly from that point on. Because Taito, I've a feeling we're not in Space Invaders anymore.

The actual shooting is intense and challenging. Enemies drift in and out for few levels, but eventually try to dash at or surprise the player from behind. Some bosses are huge and complex, while others are tricky and require a ton of patience. If you're impressed by any of them, you'll happily see them reappear later in the game, though this can seem lazy on the part of the developers. Even with rehashed bosses, though, Infinity Gene moves from between dimensions, styles, spectrums of color, weapons, enemies types, and the list goes on. In short, you won't be bored.

Infinity Gene's constant shifting and evolution elicits a lot of excitement and energy. It helps that the techno music soundtrack constantly moves with the background and sprites with near-perfect synchronization. Forcing the player to adapt to every level mirrors the adaptation Space Invaders has had to undergo to stay relevant. IG represents a sea change for all of those games the "Halo of Duty kids" never played. Cue the Centipede, Root Beer Tapper, and Xevious remixes in 3... 2... 1.

Featuring a ton of unlocks, IG keeps players busy and entertained. These earned rewards include new weapons, bonus levels, modes, and options. This unlock system evolves the player's abilities to match the progressive level designs. Don't worry if you're struggling to clear level 3-4. Play earlier levels over again and you can find yourself evolved past the enemies that previously bested you. Unlock a new weapon or an option for more stock lives and you'll be set until you hit the next wall.

Of the extra modes, music mode provides the most entertainment. By streaming music or ripping CDs to the hard drive, IG bends the sound to its will, forcing the music to react to the background, enemies, or score. Infinity Gene's soundtrack is good, but yours is better.

Rounding out the package, like every XBLA game, is Leaderboard support. Multiplayer is absent, but the old arcades were always about putting your initials next to a high score. Competitive or cooperative, multiplayer is not missed.

IG's immediate, pressing visual and audio effects can be a shock to the player's system. Immediate reactions will register on the "what the hell" scale, but with a little time, gamers will have a fluid, evolving experience that's got them on the tips of their thumbs.